[1] Between December 2012, and January 2013, photometric observations of Belgica were taken at several observatories in Italy, the Czech Republic, Spain and the United States by astronomers Luis Martinez, Lorenzo Franco, Andrea Ferrero, Petr Pravec, and Stefano Padovan.
They gave three concurring lightcurves with a rotation period of 2.709 hours and a brightness variation of 0.08 to 0.10 magnitude, indicating a nearly spheroidal shape for the asteroid's body (U=2/3/n.a.).
The photometric observations also revealed, that Belgica is a binary system with an asteroid moon, approximately 36% the diameter of its primary, orbiting it every 47.26±0.02 hours.
[7] According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Belgica measures 9.78 and 10.406 kilometers in diameter and its surface has an albedo of 0.301 and 0.273, respectively,[8][9] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and derives a diameter of 10.94 kilometers with an absolute magnitude of 12.17.
[4] This agrees with the estimated diameter of 11±2 kilometers by Franco et al.[6] This minor planet was named in honor of the state of Belgium.